JP2012170719A - Magnetic resonance imaging apparatus and method for producing magnetic field-correcting coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin shim coil capable of being easily laminated on a gradient magnetic field generation device with high position accuracy while securing necessary magnetic field intensity, and capable of reducing an error magnetic field in a stepped-down part.SOLUTION: The shim coil of this magnetic resonance imaging apparatus wherein a test subject is disposed in a magnetic space generated from a static magnetic field generation source and a gradient magnetic field application part, and which generates an image of a target portion of the test subject based on an MRI signal emitted from the test subject applied with an irradiation pulse is formed with a plurality of coil patterns on a single sheet and wiring lines connecting them, and has a wiring structure reducing the error magnetic field in each connection part of the wiring lines.

Description

  The present invention relates to a magnetic resonance imaging apparatus, and more particularly to a magnetic resonance imaging apparatus including a saddle-type shim coil that is thin and easy to mount and a method for manufacturing a magnetic field correction coil.

  As a method for manufacturing a shim coil, for example, there are a method of arranging a wire rod as described in Patent Document 1 and a method of cutting a coil pattern from a plate-like conductor by cutting or etching. The method of cutting and etching shown in the latter can form a pattern with higher accuracy than the method of arranging the wire as shown in the former.

  When a plate-shaped conductor is processed into a spiral coil shape by cutting or etching, a means for holding the coil shape after processing is required.

  In order to maintain the shape of the coil after etching, there is a method in which a laminated plate in which a conductor such as copper is bonded on a resin base material is used as an object to be etched. For example, in Patent Document 2, the method is applied to both surfaces of a resin sheet to obtain a gradient coil.

JP 2007-307034 A JP 2006-116305 A

  With the wide bore of the MRI apparatus, the gradient coil tends to be made thinner. However, the magnetic field correction shim coils, which are the contents of the gradient magnetic field coils, tend to increase the number of shim coils to be mounted as the functionality of the MRI apparatus increases. Therefore, the thinning of the shim coil has been a problem.

  In addition, a single saddle-type shim coil unit is usually formed by connecting a plurality of coils, but the wiring work becomes more complicated as the number of mounted shim coils increases. Therefore, simplification of the mounting work to the gradient magnetic field coil has been a problem.

  The content described in Patent Document 2 is that a conductor sheet is arranged on both sides of an insulating sheet with respect to a gradient coil, which is different from the shim coil which is the subject of the present invention, and is so-called connecting between the coil winding patterns. Since the position of the paragraph is different between the front and back sides, the error magnetic field is increased.

  Accordingly, an object of the present invention is to provide a shim coil that is thin while ensuring the required magnetic field strength, and can easily stack a shim coil on a gradient magnetic field generator with high positional accuracy, and can reduce an error magnetic field at a section. Is to provide.

  In order to solve the above-described problems, the main components of the magnetic resonance imaging apparatus according to the present invention are configured as follows. That is, a subject is placed in a magnetic field generated from a static magnetic field generation source and a gradient magnetic field application unit, and based on an MRI signal emitted from the subject to which an irradiation pulse is applied, the target region of the subject is In the magnetic resonance imaging apparatus for generating an image, the gradient magnetic field application unit includes a magnetic field correction unit that corrects at least one of a static magnetic field generated from the static magnetic field generation source and a gradient magnetic field generated from the gradient magnetic field application unit. The magnetic field correcting means is disposed on one main surface of the substrate and causes a current to flow to generate a magnetic field, and a magnetic field correction unit is disposed on the other main surface facing through the substrate to generate a magnetic field by flowing current. The first and second conductor portions include a region in which the direction of the magnetic field generated from the first conductor portion and the direction of the magnetic field generated from the second conductor portion are opposite to each other. It is characterized by.

  The main method of manufacturing the magnetic field correction coil according to the present invention is configured as follows. That is, a method of manufacturing a magnetic field correction coil for correcting at least one of a magnetic field generated from a static magnetic field generation source and a gradient magnetic field application unit in a magnetic resonance imaging apparatus, comprising: a step of preparing a substrate; A process of affixing a conductor sheet on the surface, a process of applying and fixing a photosensitive organic material on each surface of the conductor sheet affixed to both main surfaces, and a mask having the shape of a magnetic field correction coil on both main surfaces A process of affixing to the surface of the photosensitive organic material above, a step of exposing and developing the photosensitive organic material by irradiating light from above the mask, and using the photosensitive organic material having the developed shape as an etching mask And forming a magnetic field correction coil having a shape on both sides of the substrate by etching the conductor sheet, and after forming the magnetic field correction coil, A through hole in a fixed position, characterized in that each of the magnetic field correction coils on both sides provided with a connecting portion for electrically connecting.

  That is, the present invention is characterized in that in a magnetic field correction means, for example, a saddle type shim coil, a plurality of coil patterns and wirings connecting them are formed on a single sheet.

  As described above, the shim coil of the present invention can be thinned while ensuring the necessary magnetic field strength by forming conductor patterns on both surfaces of the resin base material. Therefore, the opening of the gradient magnetic field generator can be made larger than before while maintaining the same performance as before, or more shim coil units can be mounted while maintaining the same size opening as before. It becomes possible.

  Since the shim coil of the present invention is formed in a sheet shape, it is possible to easily stack a shim coil with high positional accuracy on the gradient magnetic field generator as compared with a conventional method of fixing a wire.

1 is a side sectional view of a magnetic resonance imaging apparatus of the present invention. Sectional drawing which shows an example of a structure of various coils. The bird's-eye view which shows the example of a saddle type shim coil. The bird's-eye view which shows the example of a spiral shim coil. The figure which shows the photolithography process (sectional drawing) of shim coil manufacture of this invention. The figure which shows the secondary processing process (sectional drawing) of shim coil manufacture of this invention. The top view which shows the example of a pattern of the saddle type shim coil of this invention. The current path schematic diagram of the double-sided pattern in the single spiral coil of this invention. The schematic diagram which shows the connection state of a back pattern and a front pattern. The developed view of the current path of the table | surface pattern seen from the front side of the shim coil unit which has the eight spiral coils of this invention. The developed view of the current path of the back pattern seen through from the front side of the shim coil unit which has the eight spiral coils of this invention. The top view of the back pattern when there is no circulation pattern.

  Hereinafter, the present invention will be described in detail with reference to the drawings together with embodiments (examples) of the invention. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment of the invention, and the repetitive description thereof is omitted.

  FIG. 1 shows a cross-sectional view seen from the side of a magnetic resonance imaging apparatus (hereinafter referred to as an MRI apparatus). As components of the MRI apparatus, there are a static magnetic field coil 1, a gradient magnetic field coil 2, a high frequency magnetic field coil 3, and a bed 4. The static magnetic field coil 1 forms a uniform magnetic field region 5. A subject (not shown) is disposed in the uniform magnetic field region 5 and lies on the bed 4. The gradient magnetic field coil 2 is fixed between the static magnetic field coil 1 and the uniform magnetic field region 5. The high frequency magnetic field coil 3 is fixed between the uniform magnetic field region 5 and the gradient magnetic field coil 2.

  The saddle type shim coil that is the subject of the present invention is usually mounted in the gradient magnetic field coil 2 and generates at least one of a magnetic field that corrects the gradient magnetic field and the static magnetic field.

  FIG. 2 shows an example of various coil configurations including a shim coil mounted in the gradient magnetic field coil 2. This figure has shown the coil structure at the time of seeing the gradient magnetic field coil 2 from the direction shown by the gaze direction (arrow) 10 of FIG. That is, the shim coil 21 is laminated via the insulating layer (1) 23 in the outer diameter direction of the main coil 22 that generates the gradient magnetic field, and further, the leakage magnetic field is passed through the insulating layer (2) 24 in the outer diameter direction of the shim coil 21. The shield coil 20 provided in order to reduce is laminated.

The main coil 22 and the shield coil 20 include coils that generate gradient magnetic fields corresponding to three orthogonal axes.
The various coil configurations described above are examples, and are not necessarily required.

  The gradient coil 2 is obtained by molding a structure such as a coil that generates a gradient magnetic field orthogonal to three axial directions and a cooling pipe that suppresses heat generation with a resin. In an MRI apparatus in which the static magnetic field is horizontal, the gradient magnetic field coil has a cylindrical or elliptical cylindrical shape and is mounted inside a magnet (usually a cylindrical superconducting coil) that generates a static magnetic field.

  Shim coils are usually resistive coils, and the static magnetic field can be corrected for each apparatus and subject by controlling the current flowing through the coils.

  Usually, a shim coil corrects a static magnetic field by generating a magnetic field having a spatial distribution corresponding to a Legendre polynomial or a spherical harmonic component. As many shim coil units as the number of components that need correction are mounted on the MRI apparatus. As the functionality of MRI increases, more shim coils are required if higher-order component magnetic field correction is required.

  The shape of the shim coil is a spiral shim coil 30 in which a spiral coil as shown in FIG. 3A is laminated along the cylindrical surface 31 of the gradient magnetic field coil and a cylindrical surface 31 as shown in FIG. There are roughly two types of spiral shim coils 32 to be layered. In the present invention, the saddle type shim coil shown in FIG.

  In order to make the coil pattern of the saddle-type shim coil thin and accurate, it is preferable to form a pattern by etching a so-called copper clad laminate having a structure in which a copper sheet is stuck on both surfaces of a resin base material.

<Example of coil pattern formation>
The procedure for creating the coil pattern of the saddle type shim coil according to the present invention will be described below.

FIG. 4A shows a photolithography process (4a to 4f) as an example of a coil pattern creation process by etching. First, in step 4a, a photosensitive organic material (resist) 41 is applied and fixed to the front and back surfaces of the material having the conductor sheet 42 attached to both surfaces of the resin sheet base material 43.
Next, a mask 44 on which the shape of the coil pattern is drawn in step 4b is attached from above the resist 41. The mask 44 is accurately aligned with the respective surfaces of the photosensitive organic material 41 fixed on both surfaces of the conductor sheet 42 at positions where the coil patterns drawn on the mask face each other.
Next, in step 4c, light 45 is irradiated from above the mask 44 to cause the resist 44 to react.
Here, in this embodiment, a type in which a region irradiated with light is dissolved by a developer, that is, a positive type resist is described as an example. However, a negative type resist can naturally be used.
At that time, the pattern formed on the mask is the reverse of the pattern used in the present embodiment and the light transmission part and the non-transmission part (so-called black and white area).
Next, in step 4d, the mask 44 is removed, and the exposed resist 46 is immersed in a solvent that dissolves, so that the resist is left in a portion that becomes a coil pattern.
Next, in step 4e, the conductor sheet 42 is immersed in a solution for dissolving it, and the portion of the conductor sheet 42 from which the resist has been removed is removed.
Finally, in step 4f, the resist 41 is peeled off to obtain a patterned conductor sheet.

  After the photolithography process (4a to 4f), the process proceeds to the secondary processing process shown in FIG. 4B.

  The secondary process in FIG. 4B will be described below.

  4A. A back-and-front connecting conductor that opens a through hole 47 at a predetermined position of the sheet base material 43 having the coil pattern 42 formed in FIG. 4A and electrically connects the coil pattern 42 formed on the back and front of the sheet base material 43. 48 is provided. Next, an insulating sheet 49 is attached to the entire back surface and the entire front surface of the sheet base material 43 so as to cover the coil pattern 42.

  When the secondary processing step is completed, the coil formed in a sheet shape is formed by winding it at an appropriate position between the structures via spacers of gradient magnetic field coils.

  The coil pattern formed on the sheet base material 43 circulates on the sheet base material 43 as shown in FIG. 5, and a coil pattern circulation part 51 that plays a role of generating a magnetic field and a coil pattern stage part 52 that connects the coil pattern circulation part 51. Composed.

  When there are a plurality of sheet base materials and they are sequentially laminated, as shown in FIG. 5, an alignment mark 53 serving as a position adjustment mark used when laminating each layer is used. The alignment mark 53 can be simplified by forming it as an etching pattern with the same conductor as the coil pattern.

  FIG. 6 shows an enlarged view of the region 500 where the coil pattern section shown in FIG. 5 is adjacent. In order to suppress generation of an unnecessary error magnetic field, the coil pattern marking part 52 is arranged such that the patterns on the front and back are overlapped and the current path 60 is in the opposite direction. That is, as shown in (a), when viewed from the front side, a current pattern 60 (shown by a solid line) flows from the right side of the figure through the coil pattern circulating portion 51a, and the coil pattern is separated from the upper portion 52a. To flow. Further, the current 60 flows through the coil pattern from the lower side of the figure and flows through the portion 52b, and flows to the left through the coil pattern circulating portion 51b.

On the other hand, as shown in FIG. 6B, when the back pattern (displayed with a dotted line) is seen through from the front side, the current 60 flows through the coil pattern rotating portion 51c from the right side of the figure and the coil Flows downward through the pattern paragraph 52c.
In addition, the current 60 is stepped through the coil pattern from above and flows through the portion 52d, and flows through the coil pattern surrounding portion 51d to the left.

Here, considering the direction of current flow, the direction of the current flowing through the coil pattern surrounding portion 51a and the coil pattern surrounding portion 51c, or between the coil pattern surrounding portion 51b and the coil pattern surrounding portion 51d is the same direction.
On the other hand, the direction of the current flowing through the coil pattern step 52a and the coil pattern step 52d, or the coil pattern step 52b and the coil pattern step 52c, is opposite.

  The magnetic field generated by the current is superimposed and doubled when the current direction is the same, but the magnetic field is canceled when the current direction is reversed. Therefore, the magnetic field is almost doubled in the coil pattern circulating portion, while the magnetic field is canceled in the coil pattern section.

  FIG. 7 shows a current path schematic diagram of a double-sided pattern in a single spiral coil. In this pattern, a through-hole is formed in the insulating sheet 43 at the innermost circumference of the magnetic field generating pattern that circulates and connected to the pattern 71 on the back surface by the back and front connection conductor (corresponding to step 4g in FIG. 4). The back pattern goes to the outer periphery while circling in the same direction as the front pattern. With such a structure, a magnetic field twice as large as when a coil is formed only on one side can be obtained.

  Next, the current flowing through the connection line connecting the coils when a plurality of coils are connected will be described below.

  A saddle type shim coil is usually composed of a unit in which a plurality of coils are connected to one magnetic field correction component. FIG. 8 and FIG. 9 illustrate development views of current paths when eight spiral coils are necessary for one shim coil unit.

  FIG. 8 is a table pattern (displayed by a solid line) viewed from the front side, and FIG. 9 is a back pattern (displayed by a dotted line) viewed from the front side. All the points indicated by alphabets (b, b ′, c, c ′, etc.) in the figure are places where the front and back patterns are electrically connected. When FIG. 8 and FIG. 9 are overlapped, b point and b ′ The points are in the same position, and the points c and c ′ are in the same position. Similarly, each alphabet corresponds in the same position.

  In the table pattern shown in FIG. 8, spiral coil patterns having a plurality of turns are arranged in order in the upper stage, and similarly, spiral coil patterns having a plurality of turns in the lower stage are arranged in order. Each coil pattern is composed of a coil pattern surrounding portion 70 and a coil pattern paragraph as a portion 90, and the coil pattern paragraph portion 90 is one coil pattern circulation portion 70 that makes one turn (one turn) and the next stage. It is a connection part which electrically connects the coil pattern surrounding part 70 which carried out 1 round (1 turn).

  First, in the upper stage in the figure, the coil pattern of the first stage on the entrance side circulates inward in order from the outside, and is electrically connected to point b ′ of the coil pattern shown in FIG. The Next, the coil pattern of the next stage on the entrance side is electrically connected at the point c ′ shown in FIG. 9 and the point c in the figure, and circulates outward from the point c (inner side) in order, and the outermost coil wiring. To. Further, the third-stage coil pattern on the entrance side, like the coil pattern shown in the first stage, circulates inward from the outside in order, and at the point d in the figure, the point d ′ of the coil pattern shown in FIG. Connected.

  Note that the outermost coil wiring around the next stage is connected to the outermost coil wiring of the third stage coil pattern by an inter-coil connection line 80.

  The fourth stage on the entrance side has the same coil pattern shape as the next stage, and the outermost coil wiring is electrically connected to the points f and f 'and connected to the back pattern shown in FIG. The

  Next, the back pattern of FIG. 9 will be described.

  Similarly to the front pattern, the back pattern is formed by alternately combining a coil pattern that wraps around from the outside to the inside and a coil pattern that wraps around from the inside to the outside. For example, the fourth coil pattern from the outlet side in the lower part of FIG. 9 connected at the point f of the front pattern has a coil pattern circulation part 71 and a coil pattern paragraph part 91, and wraps around from the outside to the inside. And connected to point g of the table pattern at point g ′. The connection between the coil patterns is connected by a coil connection line 81 as in the table pattern of FIG.

  The current is b → b ′ → c ′ → c → d → d ′ → e ′ → e → f → f ′ → g ′ → g → h → h ′ → i ′ → i → j → j ′ from the entrance. Reach the flow outlet in order.

  The shim coil unit according to the present invention is formed by superimposing the front pattern shown in FIG. 8 and the back pattern shown in FIG. 9 in the direction as shown. That is, the first-stage coil pattern of the front pattern and the first-stage pattern on the outlet side of the back pattern are superimposed at the same position via the substrate.

  At this time, as indicated by the arrows in the figure, the direction of the current in the coil pattern rotating portion 70 between the coil patterns facing each other in the front pattern and the back pattern is the same in the front pattern and the back pattern. Therefore, the magnetic field induced by the current has an effect of being superimposed and doubled.

  On the other hand, in the coil pattern paragraphs (connection parts) 90 and 91 shown in FIG. 8 and FIG. 9, the coil pattern paragraphs (connection parts) 90 and 91 are different from the coil pattern circulation part in the front and back patterns. The direction of the current in the portions (connection portions) 90 and 91 of the coil pattern paragraphs between the opposing coil patterns in the pattern is arranged to be opposite to each other. Therefore, the magnetic field induced by the current has the effect of canceling out.

  The front and back pattern coil pattern paragraphs (connection portions) 90 and 91 are arranged in parallel to each other.

  With regard to the coil pattern forming method shown in FIGS. 8 and 9, since the wiring connecting the respective coils can be formed by etching simultaneously on the back and front, one shim coil unit can be formed on a single sheet. It is.

  In FIG. 6, it is described that the pattern is arranged so that the direction of the current is reversed in the pattern section. However, in FIG. 8 and FIG. 9, the inter-coil connection that connects the coils that do not contribute to the magnetic field correction. The current paths that flow through the lines 80 and 81 are arranged so that reverse currents flow on the front and back sides, and the error magnetic field is suppressed.

  Next, a substrate on which shim coils are mounted will be described.

  Since the shim coil of the present invention is wound on a cylindrical gradient magnetic field coil, sufficient flexibility is required. For example, when a glass epoxy laminate is used as an insulating sheet of a base material, the thickness is 0.3 mm or less. It is preferable that Further, if the copper to be etched is too thick, it may be etched in the sheet surface direction and the accuracy of the pattern shape may be impaired. Therefore, the copper thickness is preferably 0.2 mm or less.

  When a plurality of shim coil units having different magnetic field components are stacked, the units are insulated so that the conductors do not contact each other. Therefore, as shown in step 4h in FIG. 4, there is a method in which an adhesive sheet based on a film such as PET (polyethylene terephthalate) is pasted after the coil pattern is formed as one of the methods for forming the insulating layer.

  Since the shim coil is mounted in the gradient magnetic field coil and molded with resin in the same manner as other structures, a large number of through holes serving as resin flow paths are provided in an insulating sheet on which no coil pattern is formed.

  A through hole for securing the flow path of the mold resin is also provided in the insulating layer. As described above, when an adhesive sheet is attached to the coil as the insulating layer, the hole is processed together with the insulating sheet that is the base material of the coil after application.

  With the above configuration, it is possible to obtain a shim coil that is thin and has good workability for stacking on a gradient magnetic field coil.

  In the second embodiment, the front pattern shown in FIG. 8 is used in the same manner as in the first embodiment, but the back pattern is different from that in FIG. That is, a coil pattern provided on one side (back side) as shown in FIG. 10 is used. The back pattern of FIG. 10 does not have a coil pattern surrounding portion, and a pattern of only the connection line 100 of each through hole is formed on the sheet base material 43.

  As described in the first embodiment, there is no current flowing in the coil pattern surrounding portion of the front pattern and the coil pattern surrounding portion of the back pattern, and there is a coil pattern surrounding portion only in the front pattern. However, they are not superimposed and doubled. Therefore, this is an embodiment applied when the magnetic field can be secured only by the current flowing in the front pattern.

  As in the first embodiment, the connecting line 100 is arranged so that the current flows in the opposite direction to the stepped portion of the spiral pattern and the connecting line between the coils. With such an arrangement, the error magnetic field is suppressed.

1 ... Static magnetic field generator,
2. Gradient magnetic field coil,
3. High frequency magnetic field coil,
4 ... Bed,
5 ... Uniform magnetic field region,
10 ... Gaze direction,
20 Shield coil (including a coil that generates a gradient magnetic field corresponding to three orthogonal axes),
21 ... shim coil,
22: Gradient magnetic field coils (including coils that generate gradient magnetic fields corresponding to three orthogonal axes),
23 ... Insulating layer (1),
24. Insulating layer (2),
30 ... saddle type shim coil,
31 ... the surface on which the shim coils in the gradient magnetic field coil are laminated,
32 ... spiral shim coil,
41 ... resist,
42 ... conductor sheet,
43 ... Resin sheet base material,
44 ... mask,
45 ... light,
46 ... Photosensitized resist,
47 ... through hole,
48 ... back and front connecting conductors,
49. Insulating sheet,
51 ... Coil pattern loop part,
52 ... Paragraph section of coil pattern,
53 ... Alignment make-up,
60 ... current path,
70: Circumferential portion of the surface pattern,
71 ... Circumference part of the back surface pattern,
80 ... Connection pattern between coils of surface pattern,
81 ... connecting wire between coils on the back surface pattern,
90 ... Coil pattern section of surface pattern,
91 ... the coil pattern section of the back pattern,
100: Through hole connection line pattern,
500 ... Adjacent area of adjacent coil pattern section,
b to f, b ′ to f ′, through holes.

Claims (12)

An object is placed in a magnetic field generated from a static magnetic field generation source and a gradient magnetic field application unit, and an image of a target region of the object is obtained based on an MRI signal emitted from the object to which an irradiation pulse is applied. In the generated magnetic resonance imaging apparatus,
The gradient magnetic field application unit includes magnetic field correction means for correcting at least one of a static magnetic field generated from the static magnetic field generation source and a gradient magnetic field generated from the gradient magnetic field application unit,
The magnetic field correction means is disposed on one main surface of the substrate and generates a magnetic field by flowing a current through a first conductor portion that is disposed on the other main surface facing the substrate. Two conductor parts,
A part of the first and second conductor portions includes a region in which the direction of the magnetic field generated from the first conductor portion and the direction of the magnetic field generated from the second conductor portion are opposite to each other. Resonance imaging device. The magnetic resonance imaging apparatus according to claim 1.
Each of the first and second conductor portions is a connection that connects a plurality of circular portions that spirally circulate on the substrate, and one of the circular portions and a circular portion adjacent to the single circular portion. And
The connecting portions are disposed on both main surfaces of the substrate so as to face each other with the substrate interposed therebetween, and currents flowing through the connecting portions on both main surfaces flow in opposite directions. Magnetic resonance imaging device. The magnetic resonance imaging apparatus according to claim 2.
A magnetic resonance characterized in that a connecting portion provided on one main surface of the substrate and a connecting portion provided on another main surface facing each other through the substrate are arranged in parallel to each other Imaging device. The magnetic resonance imaging apparatus according to claim 2.
A plurality of first conductor portions laid on one main surface of the substrate; and a second conductor portion laid on the other main surface facing the one main surface through the substrate;
The first circuit portion constituting one of the plurality of first conductor portions has a first wiring pattern that circulates inward sequentially from the outside, and the other one of the plurality of first conductor portions is When the second circuit portion to be configured has the second wiring pattern that circulates outward from the inside in order,
A third winding portion disposed at a position facing the first winding portion and constituting one of the second conductor portions has the second wiring pattern;
A magnetic resonance imaging apparatus, wherein a fourth circuit portion, which is disposed at a position facing the second circuit portion and constitutes another one of the second conductor portions, has the first wiring pattern. The imaging device according to claim 1.
The magnetic resonance imaging apparatus, wherein the first and second conductor portions are electrically connected by a connection portion disposed in a through hole provided through the substrate. The imaging device according to claim 1.
The magnetic resonance imaging apparatus, wherein the substrate is formed of a single sheet and can generate at least one type of correction magnetic field. The imaging device according to claim 1.
The magnetic resonance imaging apparatus, wherein the substrate is made of a flexible material having flexibility. The imaging device according to claim 1.
The magnetic resonance imaging apparatus, wherein the magnetic field correction means has an insulating sheet attached to the surface thereof. A method of manufacturing a magnetic field correction coil for correcting at least one of a magnetic field generated from a static magnetic field generation source and a gradient magnetic field application unit in a magnetic resonance imaging apparatus,
Preparing a substrate;
A step of attaching a conductor sheet to both main surfaces of the substrate;
Applying and fixing a photosensitive organic substance on each surface of the conductor sheet attached to both main surfaces;
Attaching a mask having the shape of the magnetic field correction coil to the surface of the photosensitive organic material on both main surfaces;
Irradiating light on the mask to sensitize and develop the photosensitive organic material;
Using the developed photosensitive organic material having the developed shape as an etching mask, and etching the conductor sheet to form magnetic field correction coils having the shape on both surfaces of the substrate,
After the magnetic field correction coil is formed, a through hole is provided at a predetermined position of the substrate, and a connection part for electrically connecting the magnetic field correction coils on both surfaces is provided. Coil manufacturing method. In the manufacturing method of the magnetic field correction coil according to claim 9,
The method of manufacturing a magnetic field correction coil, wherein the substrate is made of a flexible material having flexibility. In the manufacturing method of the magnetic field correction coil according to claim 9,
A method of manufacturing a magnetic field correction coil, further comprising a step of attaching an insulating sheet so as to cover the magnetic field correction coil after providing the connecting portion. In the manufacturing method of the magnetic field correction coil according to claim 9,
A magnetic field correction coil, wherein, when a plurality of the substrates are stacked, an alignment mark for position adjustment used for stacking the substrates is formed by processing the same conductor sheet as the magnetic field correction coil. Manufacturing method.

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